A brachial plexus injury affects the group of nerves that carry signals from the spinal cord to the shoulder, forearm, and hand. A brachial plexus injury is a stretch or, in the most severe case, a complete rupture of these nerves. This injury occurs when the shoulder is subjected to a downward force and the head is subjected to a force directed upward and away from the shoulder.
Injuries to the brachial plexus often occur during contact sports, as a result of road traffic accidents involving automobiles and motorcycles, and also from falls. In infants, the brachial plexus may be damaged as a result of birth trauma. The brachial plexus can also be affected by other diseases, such as inflammation or neoplasms.
Minor injuries may resolve on their own, but more severe cases require surgery.
1. Causes of damage to the brachial plexus
The most common injury is to the brachial plexus.
occurs as a result of shoulder injuries associated with a motor vehicle accident or a fall from a motorcycle. Of the entire spectrum of injuries to the musculoskeletal system, this type of damage accounts for 3-10%. This injury is caused by traction or impact. As a result, the limb loses sensation, mobility, or both.
Conservative therapy for the resulting disorders is rarely sufficiently effective. At the same time, sometimes during the first 3-4 months after injury, spontaneous restoration of functions can occur, especially against the background of adequate rehabilitation measures. If no positive dynamics are observed in the first six months, we have to admit that non-surgical treatment is impossible. An examination is prescribed aimed at assessing the location, nature and severity of damage to the trunks of the brachial plexus.
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Brachial plexus injuries
The article was prepared by surgeon Andrey Vladimirovich Baitinger
The brachial plexus is a collection of nerve fibers that arise from the spinal cord. These nerve fibers are responsible for the sensitivity of the skin of the upper limb and muscle function. When the nerve plexus is damaged, sensitivity is lost and the limb is paralyzed. Causes of Injuries The most common cause of injury to the brachial plexus is a motorcycle injury. Motorcycle injury is a type of high-energy injury. In addition, the cause of nerve damage can be car accidents, open wounds, tumors, etc. Types of injuries Injuries to the brachial plexus can be closed or open. When closed, there is no wound on the body, but as a result of injury, the nerves can be stretched (traction injury) or torn from the spinal cord (avulsion). These injuries most often occur among motorcyclists. Paralysis of the arm occurs instantly. With an open injury, there is a wound and possible damage to muscles, bones and other structures. Types of Injuries The brachial plexus arises from the spinal cord through the interlacing of the C5-T1 roots. The most common damage may be as follows:
- injury to the C5-C6 nerves - in this case, paralysis of the shoulder muscles occurs, flexion of the elbow joint is impaired. The brush remains functional. This type of paralysis is called Erb's palsy.
- injury to the C8-T1 nerves - in this case, complete paralysis of the hand muscles occurs, but the shoulder and elbow joints work. This type of paralysis is called Klumpke's palsy.
- injury to the C5-T1 nerves—total paralysis. In this case, paralysis of the entire limb occurs, the shoulder, elbow and hand stop working
Diagnosis If nerve injury is suspected, the patient should be examined by a specialist in nerve surgery as soon as possible. The most important thing is not to wait! There is no time to waste, because with each missed day and month the chances of restoring function become less and less. Already during the examination, a specialist may suspect the type of damage and prescribe the necessary examinations. ENMG, MRI, etc. are used as additional examinations.
- ENMG - electroneuromyography - study of the conduction of an electrical impulse along a nerve. Allows assessment of nerve function.
- MRI - magnetic resonance imaging - the study allows you to visually assess the anatomical state of the nerves. Using MRI, you can find the location of the nerve rupture, determine the separation of the roots from the spinal cord, and determine the condition of the surrounding soft tissues.
Treatment The treatment strategy consists of several points and depends on the type and type of injury, as well as the statute of limitations. It must be borne in mind that the earlier the patient applies, the higher the chance of recovery. If the nerves are not restored within 1 year after the injury, the muscles will atrophy and die. Therefore, it is necessary to carry out the full range of examinations as early as possible. Neurosurgical correction
If the muscles are not in a state of death and no more than 6 months (maximum 1 year) have passed since the injury, there is a chance to undergo surgery to restore damaged nerves. When nerves are separated from the spinal cord, nerves are moved, nerves are transplanted, etc. Such operations allow restoration of muscle control and a wide range of limb functions. Orthopedic correction
If more than a year has passed since the injury and the muscles have died, then nerve surgery becomes pointless. In such cases, a transplant of working non-paralyzed muscles and tendons is performed. Such operations are more complex and require long-term rehabilitation and retraining of the patient. Unfortunately, such operations do not compensate for the full variety of movements and functions of the upper limb. Using muscle and tendon transfers, surgeons can restore movement to the most important muscles. Rehabilitation
After any operation, rehabilitation is required, which includes physical therapy, physical therapy and electrical stimulation.
Forecasts
In cases of damage to the nerve sheath, there is a chance of self-recovery without surgery. Unfortunately, such damage is very rare. The prognosis for recovery of function depends on the type and type of injury, as well as the duration of the injury.
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2.Diagnostics of damages
An examination that allows us to draw conclusions about the structure of damage includes:
- MRI;
- CT myelography of the cervical spine;
- chest x-ray;
- stimulation electromyography;
- Ultrasound of the brachial plexus trunks and nerves.
During the diagnostic process, it is very important to establish or exclude the separation of the roots from the spinal cord.
If avulsion does not occur, then an intrastem neuroma
as an attempt to compensate for internal damage. Nerve signals are not transmitted through the neuroma.
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Complications
Over time, most brachial plexus injuries in adults and children heal without permanent damage. However, some injuries can cause temporary or permanent impairment:
Joint stiffness. When an arm or hand is paralyzed, joint stiffness may occur, limiting joint movement even though control of the limb has been restored. To achieve this, doctors usually prescribe physical therapy classes during the recovery period. Pain. The pain occurs due to nerve damage and can become chronic. Loss of sensation. If you lose sensation in your arm or hand, there is a risk of accidentally injuring or burning it and not noticing it. Muscular atrophy. Nerves recover slowly, taking several years. During this time, muscles that are not subjected to sufficient stress can atrophy. Irreversible damage. The extent of recovery from a brachial plexus injury depends on a number of factors, including age, type, location, and severity of the injury. Even after surgery, some patients experience irreversible damage, ranging from weakness in the hand, shoulder or forearm to paralysis.
3. Neurosurgical treatment
Restoration of the damaged brachial plexus is carried out surgically - by the method of neurolysis
. This operation is most effective if performed within 6-8 months after the injury. If this period exceeds 18 months, the effectiveness of neurosurgical treatment is significantly reduced due to the developing Wallerian degeneration of nerve fibers.
If the diagnostic results reveal a neuroma, then it is excised during the operation. This is a microsurgical effect (endoneurolysis). If necessary, autograft
(nerve fibers taken from the lower leg, chest, etc.). The same technique, called “neurotization,” is used when the root is torn from the spinal cord trunk.
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SHOULDER PAIN AFTER INJURY
Severe neuropathic pain syndrome of the shoulder is a rare but potentially dangerous complication of traumatic injuries to the extremities. It is one of the specific areas of treatment for chronic pain.
Avulsion of the nerve plexus is a traumatic preganglionic separation of the branches of the plexus (see Fig. 1).
Fig.1. Avulsion of the brachial plexus.
Severe pain can develop with avulsion of a nerve root at any level, but the most important clinical significance is avulsion of the nerve plexus (usually the brachial plexus), which is accompanied by severe pain in the insensitive limb. Chronic pain in the shoulder after injury with constant burning sensations and paroxysmal exacerbations develops with avulsion of the brachial plexus in 26-91% of cases. Pain may appear immediately after the traumatic injury or several months later. One study found that approximately one third of patients still had severe pain two years after injury. Stress, concomitant diseases, weather changes contribute to increased pain; in some cases, discomfort is relieved by traction or special techniques, such as squeezing or rocking the arm, or massaging the neck or shoulder. The limb is partially or completely devoid of sensitivity, but phantom-like sensations, paresthesia (tingling, burning, numbness) and others may be noted.
Differential diagnosis of nerve root damage and its avulsion is important, since in the first case nerve replacement is indicated. Typically, the diagnosis is made on the basis of cumulative clinical signs, electrodiagnostic studies and computer diagnostic results (the most important is magnetic resonance imaging, which can detect pseudomeningocele with root avulsion).
Comprehensive treatment for shoulder pain after injury aims to simultaneously relieve pain and restore function. The use of antidepressants and anticonvulsants plays an important role here. However, along with this, great importance is also attached to motor rehabilitation.
A special role in this pathology is played by surgical treatment - destruction of the dorsal root entry zone into the spinal cord (from the English Dorsum Root Entry Zone - DREZ operation).
Fig.2. Micro- DREZ -tomy.
It is necessary to take into account the fairly large percentage of complications of this operation, as well as the structure of these complications, among which the recurrence of the pain syndrome (often in an even more severe version) is perhaps the least dangerous in comparison with such complications as paresis, paralysis and dysfunction of the pelvic organs.
The initial version of this operation was extremely traumatic. In modern neurosurgery, the use of DREZ-tomy itself has already been abandoned and the so-called micro-DREZ-tomy is mainly used (see Fig. 2). The purpose of the operation is the destruction of only nociceptive fibers, i.e. conducting only pain impulses to the brain.
The operation itself is minimally invasive and is no longer performed with a scalpel, but with a laser knife, which significantly reduces trauma and the development of subsequent complications.
However, the accumulated clinical experience allows us to recommend its implementation only in cases of very intense pain.
With the advent of a new theory of the development of pain syndromes and new treatment methods, it has become possible to control pain during brachial plexus avulsion using neurostimulation methods. These include spinal cord stimulation and stimulation of the motor cortex of the brain. According to foreign literature, these methods have good efficiency (from 60% to 80%) and are minimally invasive; in addition, it is possible to test their effectiveness by test stimulation. To stimulate the spinal cord, this is percutaneous implantation of test electrodes, and to stimulate the motor cortex of the brain, this is transcranial magnetic stimulation. A more detailed description of these methods is provided in the relevant sections. Here it should be noted once again that these techniques are minimally invasive, and therefore have fewer complications, compared even with micro DREZ surgery.
In our clinic, spinal cord and brain stimulation has been used for the treatment of chronic pain syndromes for more than 10 years. You can make an appointment with us and get a comprehensive consultation on this issue. Your doctor E. D. Isagulyan is a candidate of medical sciences, an experienced neurosurgeon and algologist.
4. Results of neurolysis
The best results of neurolysis are achieved with incomplete separation of the roots of the brachial plexus trunks. There is a restoration of the functionality of the peripheral nerves and the mobility and sensitivity of the limb returns. The result is not always a complete recovery, but even partial mobility of the arm for such patients is a significant relief that improves the quality of life. This “useful” recovery after neurolysis is noted by up to 80% of patients.
It is worth noting that rehabilitation
. As a rule, muscles have time to atrophy to one degree or another. Adequate postoperative measures are designed to restore not only sensitivity, but also muscle strength, accuracy of movement and plasticity of the limb.
Injuries to the brachial plexus occupy a special place among injuries of both the upper limb and the peripheral nervous system and account for 3-5%. Treatment of this group of patients is long-term and, as a rule, requires the use of technically complex and multi-stage operations.
The socio-economic significance of this problem is undoubted, since people of working age suffer, and disability reaches 81% (Martirosyan V.V. et al., 1984; Shevelev I.N., 1990). In this regard, the problem of treating patients has not only medical, but also social significance [1-5].
The introduction of microsurgical technology into reconstructive surgery has improved the quality of nerve trunk restoration and stimulated the emergence of new techniques based on the use of surgical optics, special instruments, and ultra-thin suture material. Such techniques include autotransplantation of neurovascular muscle flaps and blood-supplied nerve grafts [6-9].
At the same time, the overall level of care for patients with brachial plexus injuries remains substandard. The reason for this is the lack of awareness among doctors about this pathology, incorrect treatment, often with an overestimation of the capabilities of conservative methods, and pessimism towards surgical treatment.
In this regard, the purpose of our study is to develop a comprehensive approach to the treatment of damage to the neuromuscular system of the upper limb due to brachial plexus injury, including surgery on the nerve trunks, microsurgical autotransplantation of tissue and known types of orthopedic correction.
Materials and methods.
The study material was presented by 304 patients with injuries of the brachial plexus who were treated in the microsurgery department of the Research Center, who underwent 354 operations.
Most often, damage to the trunks of the brachial plexus was observed in people of working age from 16 to 40 years.
Damage to the brachial plexus most often occurred as a result of road traffic accidents - 74%, the remaining 26% were due to other injuries received at work and at home.
The diagnostic complex included: clinical neurological examination, electrophysiological tests - electroneuromyography (ENMG), additional methods - studies of the main blood flow of the upper limb, radiography, NMR tomography.
The clinical picture of movement disorders varied greatly in degree and extent. When movement disorders predominated in the proximal or distal parts of the injured limb, the clinical picture of upper paralysis of the Duchenne-Erb type or lower paralysis of the Dejerine-Klumpke type was revealed, respectively. Some patients had a mosaic pattern of functional disorders. However, with severe traction injuries of the brachial plexus, total paralysis of the limb was most often observed.
The study of ENMG data during conservative treatment and the postoperative period made it possible to solve one of the objectives of this study - to substantiate the indications for surgical treatment of patients with brachial plexus injury, depending on the time period that has passed since the injury.
The determining period for making a decision on surgical intervention in patients with brachial plexus injury should be considered 4-6 months from the moment of injury in the absence of effect from conservative therapy.
The presence of preganglionic, postganglionic, or a combination of pre- and postganglionic levels of damage to the brachial plexus is an indication for surgical treatment. In case of partial damage to the brachial plexus (presence of conduction along the nerve trunks), if the muscle registers less than 30% of the CDE of the muscles of the intact limb, reconstructive operations are indicated.
Patients who underwent surgical treatment were divided into 2 groups. The first group included patients operated on at the stage of possible muscle reinnervation. The second group included patients operated on at the stage of denervation muscle atrophy. In the first group, 184 patients underwent neurolysis and endoneurolysis of the trunks and branches of the brachial plexus, and 61 patients underwent 81 reconstructive operations on the nerve trunks.
In the second group, patients underwent 90 orthopedic operations, which included transposition, transplantation of intact muscles, various types of muscle-tendon plasty, teno- and arthrodesis.
In the stage of possible reinnervation, reconstructive operations on the nerve trunks consisted of neurorhaphy of the damaged trunks, and if there was a defect between the ends of the nerve trunks, it was replaced with an autonervous graft. In case of pre- and postganglionic damage to the brachial plexus, reinnervation of the peripheral parts of the damaged trunks was carried out using neurotizing nerves, which were the motor branches of the cervical plexus, the accessory nerve, intercostal nerves, and the C7 spinal nerve of the contralateral side [10-13].
The number of neurotizer nerves is limited, so they should be used to restore the muscles responsible for providing a minimum range of motion. With upper paralysis, this is flexion of the limb at the elbow joint, abduction at the shoulder joint, as well as the function of external rotation of the shoulder, for which the musculocutaneous, axillary and suprascapular nerves are respectively responsible. In the presence of inferior brachial plexus palsy, it is necessary to restore the motor function of the anterior and posterior muscle groups of the forearm, or at least one of them. There is no need to talk about achieving reinnervation of the hand muscles in the current period of development of surgery. Reinnervation of the hand muscles occurs only in rare cases and more often in children.
In our study, restoration of the function of the biceps brachii muscle was carried out by neurotization of the musculocutaneous nerve using the intercostal nerves in 23 patients or the accessory nerve in 18 patients.
Both intercostal nerves and the accessory nerve are suitable for neurotization of the musculocutaneous nerve. We see the advantages of using the accessory nerve for neurotization of the musculocutaneous nerve in that surgical access to it is less traumatic compared to isolating the intercostal nerves, in addition, it has a large number of myelin fibers. The disadvantage of using it is that it is relatively often damaged. In addition, when using it, as a rule, there is a need to use an autonervous insert. In case of damage to the accessory nerve, intercostal nerves are used as neurotizers, firstly, in view of the constancy of their topography, secondly, because they are almost always not damaged, thirdly, when using them, it is possible to use direct neurorhaphy (without the use of autonervous inserts).
To restore the function of the deltoid muscle, neurotization of the axillary nerve was performed using the accessory nerve and intercostal nerves. The function of the rotator cuff muscles was restored by neurotizing the suprascapular nerve with the motor branches of the cervical plexus and the accessory nerve. Restoration of forearm muscle function was carried out by neurotization of the radial nerve with intercostal nerves, the median nerve was neurotized with intercostal nerves and the C7 spinal nerve of the contralateral side.
The results of treatment of patients of the first group using reconstructive operations on the nerve trunks were as follows.
The largest number of neurotizations was performed to restore the function of the biceps brachii muscle (41 observations). Positive functional results (M3-M5) with the use of intercostal nerves and the accessory nerve were obtained in approximately the same percentage of cases, 83.3% and 87.5%, respectively. However, an excellent functional result (M5) when using the accessory nerve was obtained in 75.0% of cases, and intercostal nerves in 41.6% of cases. Analysis of long-term results of surgical treatment of patients in the first group showed that “useful” restoration of the function of the upper shoulder girdle and shoulder was obtained in 82.0% of cases, and the function of the forearm muscles - in 58.0% of cases.
In the second group of patients in the stage of denervation muscle atrophy, all pathology in the orthopedic aspect was conditionally divided into 2 groups - these were patients who required restoration of the function of the muscles of the upper shoulder girdle and shoulder and patients who required restoration of the function of gripping the hand. Restoring the function of abduction and flexion in the shoulder joint was performed by transposing the muscles to the deltoid region, which was carried out by monopolar movement of the trapezius muscle. In some cases, simultaneously with the trapezius muscle, transposition of an additional muscle was performed - the latissimus dorsi muscle or the pectoralis major muscle. With monopolar movement of the trapezius muscle, only 20° of shoulder abduction and flexion was obtained. The use of two muscles made it possible to achieve shoulder abduction to 60-65° and flexion to 75-80°. In one observation, despite the simultaneous movement of two muscles, the functional result was poor, the reason for which we explain by the presence in the patient of denervation atrophy of both the deltoid muscle and the muscles of the rotator cuff and serratus muscles. Transposition of the trapezius muscle according to Saha allowed the shoulder to be abducted by 50° and flexed by 45°.
In patients with winged scapula syndrome, the pectoralis major muscle was transposed to the lower angle of the scapula and, as a result, full function of limb movements in the shoulder joint was obtained. In some cases, in addition to transposition of the pectoralis major muscle, transosseous fixation of the upper angle of the scapula to the 4th rib was performed, which made it possible to obtain the function of abduction and flexion of the shoulder by 60° and 70°, respectively.
Arthrodesis of the shoulder joint was performed taking into account the residual function of the denervated muscles, which made it possible to achieve 45° abduction of the limb in the shoulder joint. In one observation, due to non-union of the arthrodesis zone, a tight false joint was formed, which nevertheless eliminated overstretching of the joint capsule and made it possible to obtain the function of shoulder abduction by 20°.
The function of limb flexion at the elbow joint was restored by the patient by transposition or transplantation of the muscle to the shoulder. The pectoralis major and latissimus dorsi muscles were used for transposition. For free grafting, the gracilis femoris or latissimus dorsi muscle was used.
With muscle transposition, excellent and good functional results were obtained in all cases. Positive functional results after muscle transplantation were obtained in 60% of patients. Moreover, the function in these patients was assessed as satisfactory and amounted to 60% of all cases. Speaking about the advisability of using one or another type of graft to restore the function of the biceps brachii muscle, we consider the latissimus dorsi muscle to be more promising compared to the gracilis muscle of the thigh, since it has the only main source of blood supply and has sufficient strength and excursion at the same time.
To obtain the function of gripping the hand, patients had their finger extension function restored by muscle-tendon plasty; in some cases, the opposition was additionally restored and arthrodesis of the wrist joint was performed. The outcome of treatment of these patients was favorable. It was possible to obtain a volumetric grip of the hand in patients, and only in one case was there a failure of the tendon suture after muscle-tendon plasty.
The next group of patients had their finger flexion function and hand muscle function restored. In some cases, restoration of function and flexion and extension of the fingers was required. The initial functional state of the hand in these patients was more severe. These patients underwent autotransplantation of the muscle in the position of the flexors of the fingers, which was supplemented with musculotendinoplasty and opponoplasty. The remaining patients required muscle-tendon plasty, posterior capsulotomy of the metacarpophalangeal joints, elimination of contractures, and lengthening of the finger flexor tendons. Volumetric grip of the hand was obtained in all patients. A fine grip was obtained in 50% of patients.
In two patients with preganglionic damage to the brachial plexus, denervation atrophy of all muscles of the forearm and hand was present. In these most severe cases, a rough passive grip of the hand was achieved by tenodesis and arthrodesis of the hand and finger joints.
An analysis of the results of treatment of patients in group II using orthopedic correction showed that “useful” restoration of the function of the upper shoulder girdle and shoulder was obtained in 61% of cases, and hand grip in 52% of cases.
Summarizing the above clinical studies, it is necessary to conclude that when treating patients with brachial plexus damage, a comprehensive methodological approach is required, taking into account the initial state of each specific clinical case in compliance with a rational phasing of treatment.
Conclusions:
1. All patients with brachial plexus injury must undergo a thorough comprehensive preclinical examination to develop adequate treatment tactics. If there is no positive effect from conservative therapy within 4-6 months, patients should be sent to a specialized clinic for surgical treatment.
2. Surgical interventions on the trunks of the brachial plexus are advisable for up to 1 year after the injury; at a later date, in the stage of denervation-muscular atrophy, orthopedic correction of the functional deficit is indicated.
3. In the stage of denervation muscle atrophy, orthopedic correction to improve the function of the upper limb is possible at any time of treatment.
4. Orthopedic correction in the stage of denervation muscle atrophy must begin with restoring the function of the upper shoulder girdle and shoulder, and at the next stage restore the function of the hand.
A.A. Bogov, I.G. Khannanova
NICT "VTO", Department of Plastic and Reconstructive Microsurgery
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